KEY: NPIAS = National Plan of Integrated Airport Systems.
NOTES: The U.S. Department of Transportation, Federal Aviation Administrations (FAAs) National Plan of Integrated Airport Systems is composed of all commercial service airports, all reliever airports, and selected general aviation airports. It does not include over 1,000 publicly owned public-use landing areas, privately owned public-use airports, and other civil landing areas not open to the general public. NPIAS airports account for almost all enplanements. In 2007, there were about 16,400 non-NPIAS airports. Commercial service airports are defined as public airports receiving scheduled passenger service, and having at least 2,500 enplaned passengers per year.
Data are as of January 1 of each year. Runway pavement condition is classified by the FAA as follows:
Good: All cracks and joints are sealed.
Fair: Mild surface cracking, unsealed joints, and slab edge spalling.
Poor: Large open cracks, surface and edge spalling, vegetation growing through cracks and joints.
SOURCE: U.S. Department of Transportation, Federal Aviation Administration, personal communication as of December 2009 as cited in U.S. Department of Transportation, Research and Innovative Technology Administration, Bureau of Transportation Statistics, National Transportation Statistics, table 1-24, available at http://www.bts.gov/publications/national_transportation_statistics/ as of January 2010.